A gas turbine engine rotor assembly conventionally comprises a plurality of circumferentially spaced airfoils which extend radially outwardly from a rotor disc. During engine operation the rotor assembly is rotated at a high speed, thereby creating a centrifugal force acting on engine components. Axial forces are imparted to the airfoils as fluid passes through the rotor assembly. The rotor assemblies often include a dovetail or firtree attachment mechanism for coupling the engine components together and for resisting the centrifugal force acting on the components. Axial retaining mechanisms such as rabbets, bolts, tangs, pins or split rings may also be provided to counteract axial loads on the airfoil. The high-speed rotation of the rotor assembly causes a centrifugal load associated with the retaining mechanisms, which may result in vibration. In order to reduce vibration, the retaining mechanisms often have to be balanced, which incurs additional time and costs.
Accordingly, there is a need to provide an improved rotor retaining system for a rotor assembly of a gas turbine engine.